Devices of the type described in the opening paragraph for transmitting a high-definition (HDTV) picture signal are generally known. By means of, for example picture transform and coding of coefficients obtained therefrom it has been found possible to compress HDTV picture signals to a considerably lower bit rate than would be necessary for the uncompressed picture signal. Such devices will in due course provide the possibility of realising HDTV video recorders having technically and economically feasible specifications as regards their electrical and mechanical aspects and as regards the use of tapes. Video recorders for recording, editing and displaying of digital picture signals having a lower standard definition (SDTV) are, however, already produced in large quantities. For example, professional PCM video recorders which can record and play back an uncompressed digital SDTV picture signal are still available in large quantities and to an increasing extent. Also in the future, they will be considerably cheaper than HDTV recorders for a long time.
It is possible to compress HDTV picture signals to a bit rate which corresponds to that of an uncompressed SDTV picture signal. In principle, the compressed HDTV signal can then be transmitted via available SDTV channels and registered on the known PCM recorders. However, compression and decompression units (integrated or not integrated in recorders) and HDTV monitors are required for editing HDTV programs. This involves a costly investment in appropriate HDTV equipment.